I see a problem with the descriptions for the A & B Breakout shields. The A shield says the center pin is 5V and the B unit says the center pin is signal. However, the description of the B shield says that it works with most servos. This is incorrect, every servo I've used has had the power on the center pin. I just did some googling and was not able to find any examples of servos currently in production that put the signal on the center pin. Apparently older Airtronics servos were wired this way, but are not for current units.
I recommend updating the description.
Thanks,
Brad